1. Field of the Invention
The present invention relates to a demodulation technique for demodulating a received signal subjected to FSK (Frequency Shift Keying) modulation, and particularly to a carrier offset detection technique for detecting the offset of the carrier frequency between the receiving side and the transmitting side.
2. Description of the Related Art
In recent years, in order to perform transmission/reception of data among multiple electronic devices, various wireless communication systems according to various standards and methods have been proposed. For example, in the Bluetooth communication system, the carrier wave is subjected to FSK modulation using binary digital data composed of 1s and 0s as the modulation data. In such a wireless communication system, in a case in which difference in the carrier frequency (carrier offset) has occurred between the transmitter side and the receiver side, the carrier offset leads to a difficulty in precise demodulation. Accordingly, the receiver side includes a circuit which detects the carrier offset.
[Patent Document 1]
    Japanese Patent Application Laid Open No. H10-98500